A scanning electron microscopic study of the common bile duct epithelium in the rabbit during experimental biliary tract obstruction.

Complete biliary obstruction was induced in rabbits by distal ligation of the common bile duct (CBD). The epithelial surface of the CBD was studied with scanning electron microscopy (SEM) at 1-6 days post-ligation. Concomitant biochemical assessments and pressure measurements in the CBD were performed. SEM of non-ligated CBD showed that the epithelium is arranged in folds and clefts, the latter displaying interdigitating cellular processes. At 2 days post-ligation, the epithelial clefts were focally distended showing marked dehiscence of the cellular processes with exposure of the subepithelial connective tissue layer. At 4-6 days post-ligation, extensive defects in the epithelium were observed, frequently with a sharp demarcation between intact epithelium and exposed connective tissue stroma.